Core Concepts
Nanoscale
The size range of 1 to 100 nanometers (nm). 1 nm = 10⁻⁹ meters. At this scale, materials exhibit unique properties.
Carbon Nanotubes
Cylindrical nanostructures of carbon with exceptional strength, electrical conductivity, and thermal properties.
Quantum Dots
Nanoscale semiconductor crystals that emit specific wavelengths of light depending on their size.
Nanomedicine
The application of nanotechnology to healthcare: drug delivery, diagnostics, and regenerative medicine.
Molecular Nanotechnology
The ability to build structures with atomic precision through mechanosynthesis.
Worked Examples & Applications
Scale Comparison: Human hair: ~80,000 nm wide. DNA: ~2.5 nm diameter. Atom: ~0.1-0.5 nm. Nanotechnology operates between 1-100 nm, where quantum effects become significant.
Carbon Nanotube Properties: Strength: ~100x stronger than steel at 1/6 the weight. Thermal conductivity: ~6000 W/mK (copper: ~400). Electrical: can carry 1000x more current than copper per unit area.
Practice Questions
Q: Why do materials behave differently at the nanoscale? A: Quantum effects become dominant, and the surface area to volume ratio increases dramatically, leading to different optical, electrical, and mechanical properties.
Q: What is a quantum dot? A: A nanoscale semiconductor crystal (2-10 nm) that emits specific light wavelengths based on its size, used in displays and medical imaging.